Dr. Samarjeet Kaur
Lecturer, Deptt of Community Medicine
GSVM Medical College Kanpur
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Dr Samarjeet Kaur Lecturer Department of Community Medicine GSVM Medical College, Kanpur Leishmaniasis
Introduction Problem statement Epidemiological determinants Clinical features Diagnosis Treatment Prevention & Control Contents
Leishmaniasis are group of protozoal diseases caused by parasite of genus Leishmania , and transmitted to humans by the bite of female phlebotomine sandfly . They are responsible for various syndromes in humans- Visceral Leishmaniasis (Kala azar ) Cutaneous Leishmaniasis Muco-Cutaneous Leishmaniasis Anthroponotic Cutaneous Leishmaniasis Zoonotic Cutaneous Leishmaniasis Post Kala- azar Dermal Leishmaniasis LEISHMANIASIS
World Visceral Leishmaniasis : 500,000 cases of kala-azar are reported annually worldwide. India, Bangladesh, Brazil, Nepal and Sudan accounts for 90% of the global incidence. Within the countries kala-azar o ccurs among poorest communities. Problem statement
Cutaneous Leishmaniasis : Occurs in dry, semi desert rural areas of central asia , middle east north and west Africa, esp in Ethopia and Kenya. 90% of cases occurs in Afghanistan, Brazil, Iran, Peru and Saudi Arabia. Muco-cutaneous Leishmaniasis : More than 90% of cases occur in Brazil, Bolivia and Peru
India
About 130 million population is at risk of the disease Kala- azar is endemic in 52 districts in Bihar (31), Jharkhand (4), West Bengal (11) and UP (6). In India both cutaneous (ZCL and ACL) and visceral disease occur but visceral is by far the most important leishmaniasis . There is an increasing trend of this disease in India India
Zoonotic cutaneous leishmaniasis : has been discovered in Rajasthan area in 1971, total 828 cases were reported. Cases of ACL have bee reported from Bikaner city.
Epidemiological Determinants
Leishmania are intracellular parasites. They infect and divide within macrophages. About 20 different leishmania parasites have been associated with human infection. They don’t offer cross immunity of one against the other. Leishmanis donovani Kala Azar & PKDL Leishmania tropica CL Leishmania brazileinsis MCL Distinction is not absolute. Agent factors
The life cycle is completed in two different hosts- Vertebrate host – Amastigote form (LB) Insect host – Promastigote form (flagellate) Reservoir of infection : There are variety of animal reservoir (dogs, jackals, foxes, rodents and other mammals). Indian Kala- azar is considered to be non – zoonotic infection with man as the sole reservoir.
Age – all age group including infants, peak age in India is 5 to 9 years. Sex – Males are affected twice as often as females. Population movement – movement of population between endemic and non-endemic areas can result in spread of infection. Socio economic status – usually strikes the poorest of the poor. Occupation – people working in farming practices, forestry, mining and fishing have a great risk of being bitten by sandflies . Host Factor
Immunity- recovery from kala-azar and oriental sore give a lasting immunity. During active phase of disease there is impairment of cell-mediated immunity, this is reflected in the negative skin reaction to leishmanin test.
Altitude – the disease is mostly confined to the plains, it does not occur over 2000 ft. Season- the prevalance of disease is high during and after rainfalls. Rural areas – more common in rural areas as favorable conditions for breeding of sandflies exists. Vectors Development projects Environmental Factor
In India, P. argentipes is a proven vector of kala-azar . P.papatasi and P. sergenti – cutaneous leishmaniasis . Sandflies breed in cracks and crevices in the soil and buildings, tree-holes, caves etc. Overcrowding, ill-ventilation and organic matter in the environment facilitate transmission . The habits of flies is mostly nocturnal and only females bite. Vectors
In india Kala Azar is transmitted from person to person by the bite of the female Phlebotomine Sandfly . Transmission may also take place by contamination of the bite wound or by contact when the insect is crushed during the contact act of feeding Blood transfussion Contaminted syringes and needles . Mode of transmission
Indian Kala- azar has a unique epidemiological feature of being Anthroponotic ; human is the only known reservoir of infection Female sandflies pick up parasite ( Amastigote or LD bodies)while feeding on an infected human host. Parasite undergo morphological change to become flagellate ( Promastigote or Leptomonad ), development and multiplication in the gut of sandflies and move to mouthparts. Healthy human hosts get infection when an infective sandfly vector bites them Transmission
Visceral leishmaniasis (VL), also known as kala-azar is fatal if left untreated in over 95% of cases. It is characterized by irregular bouts of fever, weight loss, enlargement of the spleen and liver, and anaemia . Darkening of the skin of face, hands, feet and abdomen is common in India ( kala-azar =black sickness) Lymphadenopathy may also occur. Clinical features
Post- kala - azar dermal leishmaniasis (PKDL) is a sequel of visceral leishmaniasis that appears as macular, papular or nodular rash usually on face, upper arms, trunks and other parts of the body. It occurs mainly in East Africa and on the Indian subcontinent, where 5–10% of patients with kala-azar develop the condition. It usually appears 6 months to 1 or more years after kala-azar has apparently been cured, but can occur earlier. People with PKDL are considered to be a potential source of kala-azar infection.
Cutaneous leishmaniasis (CL) causes skin lesions, mainly ulcers, on exposed parts of the body, leaving life-long scars and serious disability. Several forms have been described – ACL, ZCL, DCL etc. The disease may be mistaken for leprosy.
Mucocutaneous leishmaniasis leads to partial or total destruction of mucous membranes of the nose, mouth and throat.
Leishmania -HIV co-infection Leishmania -HIV coinfected people have high chance of developing the full-blown clinical disease, and high relapse and mortality rates. Antiretroviral treatment reduces the development of the disease, delays relapses and increases the survival of the coinfected patients. High Leishmania -HIV coinfection rates are reported from Brazil, Ethiopia and the state of Bihar in India.
Recurrent fever loss of appetite, pallor and weight loss with progressive emaciation, weakness. Skin - dry, thin and scaly and hair may be lost. persons show grayish discolouration of the skin of hands, feet,abdomen and face which gives the Indian name Kala azar meaning "Black fever" Signs and Symptoms
Splenomegaly . Hepatomegaly . Lymphadenopathy . Anaemia - develops rapidly. Anaemia with emaciation & gross splenomegaly produces a typical appearance of the patients.
PKDL Occurs several years after the apperant cure of kala azar , signs symptom includes lesion consists of multiple nodular infiltrations of the skin usually without ulceration, parasites are numerous in this lesion. CL,ACL,ZCL, etc here agent is restricted to skin, painful ulcer in the parts of body exposed to sand fly bites, reducing the victims ability to work
Clinical Most infections are diagnosed clinically. The patient has an irregular fever, anemia, and leukopenia ; hepatosplenomegaly and bone marrow suppression are characteristic. Lab invest Haematological findings viz Anaemia , leucopenia, thrombocytopenia & hypergammaglobulinemia . WBC : RBC ratio is 1:1500 or even 1:2000 Raised ESR . Diagnosis
Parasitological Aldehyde (Napier) test Serological test Leishmanin (Montenegro) test Haematological findings Laboratory diagnosis
Parasitological diagnosis The demonstration of the parasite LD bodies in the aspirates of spleen, bone-marrow, lymph nodes or in the skin (in case of CL) is the only way to confirm VL or CL. However, sensitivity varies with the organ selected for aspiration. Spleen aspiration has the highest sensitivity and specificity (considered gold standard)
1 to 2 ml of the serum from the case of kala-azar is taken and a drop or two of 40% formalin is added. Jellification to milky white opacity (like the white of hard boiled egg) so that in ordinary light newsprint is invisible through it, is considered positive. This test is good for surveillance but not for diagnosis. The test is non-specific as it becomes positive in many other chronic infections in which albumin to globulin ratio is reversed. Aldehyde Test of Napier
Serology tests: Direct Agglutination Test (DAT), rk39 dipstick test, ELISA and indirect fluorescent antibody test (IFAT) are available. rk39 – rapid diagnostic test is based on the recombinant k39 protein. It is an epitope apparently conserved on amastigote of Leishmania species that cause visceral infection.
Control the reservoir Treatment of the cases Sand fly control Personal prohylaxis Active and passive detection of the cases and treatment of those who found to be infected. House to house visit. Mass surveys in endemic areas for early detection of the cases. Control measures
Treatment of Cases
Treatment Pentavalent antimony---- Sodium stibogluconate 10mg/kg body wt for 20 days in adults. 20mg/kg body w in childrens . Pentamidine isethionate 3mg/kg body wt for 10 days. Amphotericin B 1mg/kg body wt IV 15 to 20 Injections alt dys Miltefosine , 2.5 mg/kg body wt in two divided doses for 4 week
Sandfly controle DDT Insecticide spraying at human dwellinngs and all animal shelter and other resting places up to the height of 6 feets from floor level Sanitation measures Personal prophylaxis
The strategy of kala azar contorl broadly includes three major activities Interruption of transmission for reducing vector population by undertaking indoor insecticidal spry twice annual major activities Early diagnosis and treatment of the kala azar cases Health education for the community awareness Kala azar control programme
In view of the success achieved so far, National health policy envisages kala azar elimination by the year 2010. The tenth five year plan targets are prevention of death by kala azar by 2004 by annual reduction of least25% zero level incidence by 2007 with atleast 20% annual reduction using 2001 as a base year, Elimination of kala azara by 2010. To achieve this government of india has provided 100% central support from the year 2003 2004 cont
Kala- azar Control Efforts in India An organized centrally sponsored Control Programme launched in endemic areas in 1990-91. Government of India provided kala-azar medicines, insecticides and technical support. State governments implemented the programme through primary health care system and district/zonal and State malaria control organizations and provided other costs involved in strategy implementation.
Programme strategy Vector control through IRS with DDT up to 6 feet height from the ground twice annually. Early Diagnosis and Complete treatment of the cases. Information Education Communication Programme intensified in 1991-92 which led to improved case registration through primary health care system. Within 3 years of intensification (1995 as compared to 1992) 70.66% decline in annual incidence 80.48% decline in deaths By 2003 as compared to 1992 76.38% decline in incidence 85.20% decline in deaths.
KALA-AZAR ELIMINATION INITIATIVE In addition to kala-azar medicines and insecticides, cash assistance is being provided to endemic states since December 2003 to facilitate effective strategy implementation by states. State/District Action Plan for Kala- azar Elimination . Template for developing District Action Plan (Kala- azar ) . Draft Communication & Media Plan for Kala- azar Elimination . Patient Coding Scheme . Kala- azar Treatment Card . Monthly Kala- azar Reporting Formats .